1. Field of the Invention
This invention relates to the field of electrical hardware and more particularly to an electrical buss strip which interconnects a plurality of spaced-apart pin contacts or terminals in the assembly and construction of electrical circuit boards.
2. Brief Description of the Prior Art
In the manufacturing and assembling of electronic circuit boards, it has been the conventional practice to employ a block or foundation of electrically insulating material for supporting a plurality of electrically conducting terminals arranged in fixed spaced-apart relationship and wherein the electronic components and circuitry or assemblies are mounted therebetween or thereon. A conventional form of terminal comprises an elongated member generally stamped from sheet material and consisting of an elongated pin portion provided at one end with a U-shaped lug or other lug configuration at the other end. The circuit board generally provides for the pin side of the terminals to project from one side of the circuit board so that various wiring and external circuit conductors may be wire wrapped to the pin side of the terminal.
In some electrical circuits, it is required that many terminals be connected to one another by a common strip or line for purposes of grounding, thermal conductivity, common power supply, etc. Such strips are known as buss strips or bars. One conventional buss strip currently in use is simply an uninsulated wire which has been cut to desired length and held against the terminals temporarily until permanent solder connections to the terminals can be made. Using a wire for buss strip purposes is time consuming in production assembling operations since some means are required for temporarily retaining the wire in place. Also, the wires often fall from their positions on the circuit board and must be reinstalled.
Another conventional buss strip, such as disclosed in U.S. Pat. No. 3,582,864, overcomes the inherent temporarily retaining problem by employing a plurality of folded-over metal leaf clamps which are connected together by a common strip. It is attached to the circuit board by clamping each leaf of the plurality to a separate pin on the wiring side of the circuit board. Each metal clamp is provided with a small aperture to receive the pin portion of the terminal and the folded metal portion of the clamp is sufficiently resilient to grip the pin portion of the terminal as the strip is installed.
However, difficulties and problems have been encountered when employing such conventional buss line or strip devices which are due to the fact that inadequate electrical and mechanical contact is made between the leaf portion of the clamp and the terminal. For example, the leaf portion is flat and rests against the flat side of the pin. However, when round terminals are employed, the flat side of the leaf nearly touches the rounded terminal at a single point. Such a single point contact creates a hot spot when high currents are employed and, the remaining surface area of the leaf is of no value as a contact at all. Furthermore, the aperture provided in the leaf-clamp device for receiving the pin is not employed in retaining the clamp onto the pin. The aperture is merely a hole which permits the clamping device to be placed onto the pins but in no way serves to effect a mechanical friction or grip separately or in combination with the leaf spring portion of the device.
Therefore, a long standing need has been established to provide a buss line or connector that will readily grip and clasp with each of the respective pins so that adequate mechanical and electrical connection is made.